South Korean President Park Geun-hye vowed Friday to deal strongly with North Korean provocations as tensions on the divided peninsula have risen sharply with the communist nation making harsh war threats day after day.

"Our current security situation is very grave. North Korea pressed ahead with a nuclear test and long-range missile development, and is threatening to nullify the Armistice Agreement," Park said during a joint commissioning ceremony for graduating military cadets at the Gyeryongdae military headquarters in central South Korea.

The Armistice Agreement refers to the cease-fire deal that ended the 1950-53 Korean War.

"I will devote all my efforts to making the Republic of Korea a prosperous and strong nation with robust security. I will deal strongly with North Korea's provocations," she said, using South Korea's official name.

Park said that any country is bound to face "self-destruction" if it concentrates only on strengthening its military power, such as nuclear weapons, when its people are starving, an apparent reference to North Korea.

Still, she held out the prospect of engagement with the North if Pyongyang "comes out on the path toward change," saying she is ready to pursue her "Korean Peninsula trust process" that calls for greater exchanges and dialogue so as to build trust and reduce tensions with the North.

Park also pledged to further strengthen defense cooperation with the U.S. 

"On the background of us enjoying freedom and prosperity today is the robust security backing, including the Korea-U.S. alliance," she said. "The new government will actively strengthen defense cooperation with friendly nations and further strengthen our self-defense capabilities."

North Korea has sharply escalated bellicose rhetoric in recent weeks in response to annual military exercises that South Korea has been holding jointly with the United States and international efforts to punish the regime for its third nuclear test.

Pyongyang has threatened to scrap the Korean War cease-fire agreement, turn Seoul and Washington into a "sea of fire" and launch a "preemptive nuclear strike" against "aggressors." It also warned that "a second Korean War is unavoidable."

On Friday, the North said it is ditching all nonaggression pacts with the South as well as a joint denuclearization pledge, while severing a hot line that was set up with South Korea at the truce village of Panmunjom.

"All the service personnel and people of the DPRK (North Korea) will turn out as one and mercilessly wipe out the aggressors and provocateurs," Pyongyang's Committee for the Peaceful Reunification of Korea said in a statement carried by the country's official Korean Central News Agency.

"We will never miss the golden chance to wage a great war for national reunification," it said.

The statement came hours after the U.N. Security Council unanimously adopted a new sanctions resolution aimed at punishing the North for carrying out an underground nuclear test on Feb. 12.

The blast came two months after it carried out a banned long-range rocket launch.

On Friday, South Korea held a meeting of senior security officials to discuss the tensions. Senior presidential foreign affairs and security adviser Ju Chul-ki presided over the meeting with top officials of the defense, foreign affairs and unification ministries as well as the National Security Service.

Upon returning from the ceremony, Park headed directly to the crisis management room at the presidential office Cheong Wa Dae to receive a briefing on the results of the security meeting, officials said.

During the briefing, Park denounced the North for making what she called "inexpressible threats" to South Korea, and instructed officials to make sure there isn't even the slightest hole in defense readiness, her spokesman Yoon Chang-jung said.

Park also instructed officials to keep a close watch over North Korea and ensure strong joint readiness with the U.S. military to "immediately incapacitate any North Korean provocations," the spokesman said.

She also asked officials to use the crisis as an opportunity to reassure the public that there is no hole in the military and security readiness in the face of threats from North Korea under any scenarios, he said.

Senior secretary Ju told reporters South Korea is fully prepared to cope with any provocations.

During the commissioning ceremony, Park was wearing the same khaki coat that she wore for her inauguration ceremony last week.

It is a color suggestive of military uniforms, possibly symbolic of her being the commander-in-chief of South Korea's armed forces.

Park, a daughter of late Army general-turned-President Park Chung-hee, praised the military for having played the role of a driving force in South Korea's development and industrialization from the ashes of the Korean War.

The military "laid the groundwork for government foundation during the chaotic period after liberation (from Japan's colonial rule), defended the country from numerous security crises, including the Korean War, and contributed to industrialization and economic development," she said.

"Now, the military is lifting the status of the country by contributing to human peace in many corners of the world," she said. "As president of the Republic of Korea, I take great pride in the moments of history that our military has defended." (Yonhap News)